1. Field of the Invention
The present invention is directed generally to automated self-scooping litter boxes, and, more particularly, to a novel and improved method of initiating a scooping or cleaning cycle therein.
2. Description of the Related Art
Cats, which are among the most popular types of domestic pets, are usually trained to use a litter box for elimination of both liquid and solid wastes. A cat litter box is normally made of a re-useable plastic or like material. Such a material does not allow a cat's urine to leak through the box, while at the same time provides an efficient, cleanable and reuseable waste container. Most cat owners take appropriate action to discard the litter from a cat litter box after an appreciable period of time, often several days. On the other hand, even before the litter has been thoroughly saturated with wastes from the cat or cats that use it, a cat may be inclined to push some of the litter out of the box, particularly if the odor is strong. In any event, the person using a cat litter box, usually the owner of the cat or cats, may find the task of emptying the cat litter to be personally obnoxious.
A number of prior art devices have been proposed for automating the cleaning of cat litter boxes; devices of this kind are disclosed in U.S. Pat. No. 4,096,827, U.S. Pat. No. 4,117,804, U.S. Pat. No. 4,190,525, U.S. Pat. No. 4,325,325, U.S. Pat. No. 4,325,822, U.S. Pat. No. 5,226,388 and U.S. Pat. No. 5,048,465.
Typical of these self-cleaning cat litter box designs are to utilize a rake or comb that is moved through the litter, periodically. The rake encounters and discharges any clumps collected by the comb into a disposal receptacle.
Of considerable relevance is U.S. Pat. No. RE36,847, issued in the name of Waters, for an improved automated self-cleaning litter box for cats, of the kind having a comb that is driven forward through the litter to a discharge end of the chamber where the clumped litter is then discharged from the litter box. The improvement of the '847 reference is focused primarily around a sensor for sensing the presence of a cat in the litter chamber, in which a photo electric sensor is preferred, but an infra red, weight, or even an audible sensor can be used. A delay device actuates the comb drive a predetermined time interval after the sensor ceases to sense the presence of a cat in the litter chamber.
As typified by the '847 reference, sensing the presence of the pet can be an important consideration, given a particular design for such an automated litter box. If the comb driving mechanism pushes the litter out of the box to a discharge end (as in the '847 reference), when the comb drive mechanism returns is can cause a potential impingement hazard to an animal that may be in the way. Similarly, if the scooping mechanism retrieves and stores the waste in a laterally articulated fashion (as in the U.S. patent application Ser. No. 11/708,368), a similar impingement hazard can occur. In order to prevent such a hazard, various strategies of sensor in combination with timers have been employed. However, all such strategies so far developed cannot accurately determine when to initiate an automated cleaning or scooping cycle, i.e. after the litter box has be used, but only after the animal has exited.
A search of the prior art did not disclose any patents that read directly on the claims of the instant invention; however, the following references were considered related.
U.S. Pat. No. 7,230,539, issued in the name of Klein, teaches a “Pet Identification Tag with Internal Cavity for Transponder Capsule”, wherein a pet tag comprises an internal cavity that removably contains an FRID capsule transponder wrapped in a thick paper having a thin layer of metal that shuts out electromagnetic fields, so that consumers can select tracking options.
U.S. Pat. No. 6,283,065, issued in the name of Shorrock, et al., teaches a collar stud attachable to a pet collar to function as an identification device with two modes: (1) a visually discernible identification code; or, (2) an RFID transponder device programmed with a unique code so that the stud serves as an electronic identification tag for the host animal. The code is made part of the data records at a health care database to aid in locating a lost pet. The electronics may further promote feed control, wherein the dish opens to allow the pet to feed with it is in proximity.
Further, radio-frequency identification (RFID) tags or transponder device are commonly available and utilized to store and remotely retrieving data. An RFID tag is an object that can be applied to or incorporated into a product, animal, or person for the purpose of identification using radiowaves. Some tags can be read from several meters away and beyond the line of sight of the reader. Most RFID tags contain at least two parts. One is an integrated circuit for storing and processing information, modulating and demodulating a (RF) signal and can also be used for other specialized functions. The second is an antenna for receiving and transmitting the signal. A technology called chipless RFID allows for discrete identification of tags without an integrated circuit, thereby allowing tags to be printed directly onto assets at lower cost than traditional tags. RFID tags come in three general varieties: passive, active, or semi-passive (also known as battery-assisted). Passive tags require no internal power source, thus being pure passive devices (they are only active when a reader is nearby to power them), whereas semi-passive and active tags require a power source, usually a small battery.
While the present invention anticipates the use of a self scooping or otherwise automated litter box having a sensor initiated automation cycle incorporated into this invention in combination, other elements and improvements are different enough as to make the combination and improvement distinguished over the these references and the inventors' own prior art.
Consequently, a need has been felt for providing an apparatus and method of accurately and safely initiating the automation cycle of such devices.